Generally tried to make them more reliable and execute quicker.
They all now load the listen script as a trick to make sure input
sources are fully read, but also terminate() at appropriate times
so that they don't take more time than needed. They're also all
serialized with the 'comm' group so listening on a port doesn't
interfere with the communication tests.
support reading from commands by adppending | to the filename.
support streaming reads from command.
Fix something to make rearead work better. (magically happened)
